JADE DESIGN IMPLEMENTATION

AUDIO CIRCUITS

After having been on the market less than a year the Opal preamp has been accepted as the leading edge in sound reproduction. We have developed the Jade to mimic it as close as possible, while making it more affordable to a wider audience. We've retained the grounded grid configuration which we deem to be the best possible circuit topology for line level amplification. Having only one buffered output allowed us to reduce the tube count to three double octal based triodes. This circuit, like the Opal, maintains an exceptional bandwidth that extends well beyond 250,000Hz. Our primary design philosophy that less is better than more has been fully developed in the Jade preamp.

POWER SUPPLY

The power supply is built on a separate terminal board, and is somewhat different from the Opal in that we have implemented passive shunt regulation of the 200 volt DC supply. It uses a double p (pi) RC type filter and a 30 watt Zener diode network to shunt the current while stabilizing the DC voltage level. We have again avoided using active feedback in order to maintain the speed of the power supply in relation to the extremely fast analog circuitry. Stability is ensured by the use of a large electrolytic reservoir capacitor and speed is enhanced by using a large (30µf) polypropylene film capacitor as a final filter stage located directly on the analog terminal circuit board. The Jade 200 volt DC power supply completely eliminates all noise and ripple to below what our test instruments can detect. An AC power line filter is also used to prevent unwanted noise and hash from entering into the unit.

PARTS

We use precision quality parts throughout. Our fixed terminal hand crafted circuit boards are identical to the ones used in constructing the Opal preamp and Topaz amplifier. The ease of replacing parts and the tenfold increase in lifetime durability are added benefits resulting from this board construction. These boards are held elevated from the surrounding metal chassis to avoid any capacitive coupling between components. We import from Denmark our stepped ELMA volume controls that use 0.1% precision metal film surface mount resistors that is second best in life expectancy only to the Shallco military switches used in the Opal.

Since perfection is our goal, we don't think parts should impart a signature sound but rather allow the sound to flow through unaltered. The type of parts used therefore must have a synergistic relationship to the circuit they are placed in. It is this relationship of which type of part to use where, that ranks our products apart from the crowd!


Jade : SPECIFICATIONS